Lack of Interest Primary Secondary User Group Display Option

It'd be great to have the option as a user to change what your primary user group to display is.

Example: If you have user groups for different name colours with user upgrades, once you've bought two - it'll just display the most recent one bought. Have an option in personal details to decide which secondary user group to display (if they have the same priority). If not, this'd make a great addon^

User groups aren't exposed on the front end. They also often wouldn't make sense to users - on my site I have groups set up for specific purposes that the users wouldn't understand.

As an admin I wouldn't want users messing with an option like this. Also I'd be setting up user upgrades appropriately to reflect the importance of an upgrade, so a user group colour would have more importance over another abd therefore should not be overridden.